LONDON (Reuters) - The United Kingdom reported 51 new COVID-19 deaths on Thursday, taking the seven-day total to 320, a drop of 38.5% compared with the previous seven-day period, official data showed. The daily number of new cases was 4,479, with the seven-day total at close to 32,000, down by 16.7% over the previous seven days, the data showed. A total of 31.147 million people have had at least one dose of a COVID-19 vaccine, while 4.513 million have had a second dose.